The present invention relates to the functionality of a system periodically changing in time and, more specifically, to a method and apparatus for establishing a performance scale for determining functionality of the system on the performance scale.
For the cardiocirculatory system functionality is usually inferred by relating maximal or minimal values of the periodically changing hemodynamic parameters during one cycle to an empirically derived surrogate range of normalcy. The empiricism associated with the surrogate range of normalcy provides for ambiguous patient diagnosis. Absent is a cardiocirculatory performance scale descriptive of the functionality of the cardiocirculatory system to measure objectively and quantitatively human performance.
Disclosed in U.S. Pat. No. 5,370,122 is a method to establish the synergy of several hemodynamic parameters from which to deduce functionality. Also, U.S. Pat. No. 5,810,011 discloses a method to measure the synergy of several different parameters to deduce functionality for display in a single reference frame. Both disclosures fail to describe functionality with specificity on a performance scale.
It is therefore an object of the present invention to provide a cardiocirculatory performance scale for hemodynamic parameters to measure human performance on said scale and to display functionality in a performance diagram.
It is a further objective of the present invention to identify basal units on the performance scale for hemodynamic parameters to allow measurements of hemodynamic parameters in basal units for display in a performance diagram.
It is still another object of the present invention to determine zones of criticalities for sustenance of life, myocardial impairment, myocardial fitness, dysfunctions from the human performance scale for diagnosis of cardiocirculatory compliance and failure, for improvement and/or deterioration of cardiocirculatory status, and for design and monitoring therapeutic interventions.
According to the present invention, there is provided a diagnostic device and method for diagnosis of the functionality of the cardiocirculatory system of an individual, measured on a performance scale, and displayed in a performance diagram said scale and performance diagram to be used for diagnosis of myocardial fitness, myocardial impairment, dysfunctions, critical illness, cardiocirculatory compliance, cardiocirculatory failure, improvement and/or deterioration of cardiocirculatory status, and outcome. The device includes the combination of sensors responsive to physiological parameters of an individual changing in time, collectively referred to as A, at an initial time t1, denoted, A1 and at a subsequent time t2, denoted A2, means to transmit A to a computer for computing the magnitudes of A at various times, the difference of the magnitudes of A at various times, the ratio of the change of A at various times in relation to the magnitude of A at an initial time, and the time trend of the computed parameters. The computer further includes sensors responsive to pre-selected magnitudes of A which are fractions or multiples determined from a standard signal A under standard conditions to serve as basal unit, on a cardiocirculatory performance scale and to establish zones of criticalities. Still further, the computer includes means for comparing the measured signal A with its standard to produce a signal A* which expresses signal A in basal units for display on the cardiocirculatory performance scale for determining functionality, said functionality comprising myocardial fitness, myocardial impairment, dysfunctions, critical illness, cardiocirculatory compliance, cardiocirculatory failure, improvement and/or deterioration of cardiocirculatory status, and, outcome, where said diagnosis is derived by reference to the zones of criticalities and the time trend of the computed parameters. The device further provides means for selecting therapeutic interventions, depending on the attainment of zones of criticalities, displays and monitors for recording improvement or deterioration by departing or approaching the zones of criticalities, recording means, audible and visible warning means activated upon the establishment of pre-selected values to warn of criticalities, and modems for transmission to a central storage facility.